Chemistry help needed here plz?

Question

The standard heats of formation of all elements in their standard states (e.g., Iron as a solid, Hydrogen as a gas, etc.) are all set at exactly zero (0). If we changed these values to, say, 30 and uniformly add 30 to all standard heats of formation would chemistry go wrong? Why? Please explain your answer.

thats the question and i absolutely dont get, all i know is that it related to Hess's Law and Thermodynamics, could some explain to me what standard heats of formation and Hess's Law

Answer 1

Standard heat of formation is used to tell us how much energy it requires to create a compound from the base components.

For example, to create CO2:
C + O2 -> CO2

Add up the heats of formation:
0 + 0 -> -393.509 kJ/mol

So you can see that were you to take 1 mole of Carbon and 1 mole of Oxygen to form CO2, it would release 393.509 kJ of energy.

Hess's law says that the amount of energy released by or required for a reaction may be determined via the heats of formation of the products and reactions:

ΔH=ΔHcP - ΔHcR
where:
ΔH = energy released (positive) or required (negative)
ΔHcP = total of the heats of formation of the products
ΔHcR = total of the heats of formation of the reactants

Here's the key to your answer: heat of formation is based on the elements that are used to create the product or reactant - and you must conserve mass (the same amounts of each element entering the reaction must come out).

Answer 2

No, chemistry will not go wrong.